Basically, it is luck of the draw ... but if a player thinks he is realistically in the top 2 players in a position, he is likely not going to want to RS.
Although some times they still do accept.
The good news is, if you apply the RS and his WE goes down, take off the RS and it returns to normal.
This means you can try several different players to find one who accepts the RS without impact to the players you take the RS off.
If a player's WE goes down initally, he will always "not accept" the RS .. so the way it used to be ... try several times until he possibly accepts, no longer works. Once upset, always upset.